1. Field of the Invention
The present invention relates to a display unit mounted on a motor vehicle.
2. Related Art
A conventional display unit of such a type is disclosed in Japanese Patent Application Laid-open No. 2001-191816, which was proposed by the same applicant as the present application.
FIG. 14 is an explanatory view showing a general configuration of a screen of the conventional vehicle-mounted display unit. The display unit watches abnormal states of a battery, a radiator, and an engine which are disposed in a bonnet of a motor vehicle. The system has a warning indication area 103 that selectively turns on each of warning symbols 103a, 103b, 103c, and 103d for warning an abnormal state of a charge quantity of the battery, a cooling water of the engine, a lubricating oil pressure of the engine, or an electronic control process of the engine. The screen indicates not only a specified content of an abnormal state but also the position of an associated instrument. For example, it is shown that the abnormality has occurred in the bonnet by turning on a bonnet position mark 101b arranged on a vehicle profile 101a of a warning position recognition area 101. The screen has an area 105 for indicating instruction illustrations 105a, 105b, and 105c to repair the warned instrument if necessary.
Furthermore, Japanese Patent Application Laid-open No. H-9-23122 discloses another vehicle-mounted display unit. FIG. 15 is an explanatory view showing screen pages of the display unit.
The display unit has a display 210 for sequentially indicating instructive illustrations on a screen 211. Each illustration has an image and instruction keys, and an oral instruction is also provided as additional information.
For example, FIG. 15 shows steps for fitting a chain on a tire of a motor vehicle. The unit displays the steps sequentially on the screen 211 and gives oral instructions associated with an image instruction of each step. FIG. 15A shows an initial step on the screen 211 for setting the chain on the tire, and the unit gives a message to prepare the chain for the tire. FIG. 15B shows a next step for laying the chain on the tire, and the unit gives an oral instruction for putting the chain on the tire. FIG. 15C shows a further next step on the screen 211 for winding the chain on the tire, and the unit gives an oral instruction for the winding process.
Furthermore, each screen page indicates a previous page key 224′a, a pause key 224′b, a next page key 224′c, and a menu key 224′d all at once. For example in FIG. 15B, the previous page key 224′a can change the screen to show the previous page of FIG. 15A. The next page key 224′c functions to indicate the next screen page of FIG. 15C. The pause key 224′b functions to keep the same image, and a repeat key 224′e is indicated in place of the pause key 224′b until one of the other keys is operated. The repeat key 224′e is also associated with an oral instruction repeatedly given. The menu key 224′d functions to indicate an instruction menu including handling of a tire chain on the screen regardless of the sequence of the screen pages.
Further another conventional vehicle-mounted display unit is disclosed in Japanese Patent Application Laid-open No. H-11-271100. FIGS. 16A and 16B show the display unit. As shown in FIG. 16A, the display unit has two indication units 72, 73. Each indication unit 72 or 73 has a pointer 52 driven by a driving unit 51 for analog indication of measured values. The indication units 72, 73 are disposed on a single meter board 58. The meter board 58 has also an illumination portion 78. Each indication unit 72 or 73 has a predetermined scale 53 arranged on the meter board 58. Inside each scale 53, there is disposed a display 54 surrounded by the scale 53. Scale numerals 55 are indicated on the display 54. In the left indication unit 73, the scale numerals 55 show engine revolution rates, while in the right indication unit 72, the scale numerals 55 show running speeds of the vehicle. The scale numerals 55 can be changed in indication range and scale unit. The scale numerals 55 can be added with marks including a speed limit mark 79 and a revolution warning mark 80. Thereby, the indication unit can show a vehicle running speed with either of km/hour or mile/hour unit without mechanical modification and another printed marks. Furthermore, the display 54 has other indication areas, for example to show a fuel residual quantity or an expected running distance 71.
The scale numerals 55 and a top 56 of the pointer 52 are arranged so as to be opposed to the markings of the scale 53. Thereby, the analog meters of the indication units 72, 73 are convenient to recognize the revolution or the running speed.
The indication unit 73 has a driving unit 51, a pointer shaft 57, and a driving shaft 59 which are incorporated with each other to compose a component. Therefore, the display 54 is formed with a through hole for engaging the display 54 with the component via the driving shaft 59. The display 54 is a liquid crystal dot-matrix one. The pointer 52 is connected to the pointer shaft 57 through a pointer hub 63 and further to the driving shaft 59. Thus, the driving shaft 59 turns the pointer 52 around a central axis 62.
The analog meter of the indication unit 72 has a driving unit 51 spaced from a central axis 62. The indication unit 72 has a driving shaft 59 which drives a shaft 57 of a pointer 52 through a driving member 60 like a belt. The driving member 60 is covered by a plate 61 not to be visible from the front side. The cover plate 61 also covers the pointer 52 when the pointer 52 is not working. Likewise, the indication unit 73 has a cover plate 61. The driving units 51 of the indication units 72, 73 are positioned in the rear side of the meter board 58 as shown by dotted lines in FIG. 9A.
FIG. 16B shows another control state of the indication unit 73 of FIG. 16A. The pointer of the indication unit 73 is in its rest state to be positioned behind the cover plate 61. The display 54 is used for providing other operational information of the vehicle. The display 54 has an indication area 69 for specifically showing gear position of an automatic gear unit. The display 54 is no longer used for showing engine revolution unlike FIG. 16A, but the display 54 functions to show a warning indication 70 showing overheat of a catalyst in an exhaust gas system. For clearer warning, the warning indication 70 is, for example, of a fluorescence color which is distinguished from the color of the revolution meter shown in FIG. 16A. The speed meter of the indication unit 72 has an additional indication area 67 and another additional 68 showing a running distance of the vehicle.
However, the conventional display system of FIG. 14 is disadvantageous in design of a meter and an instrument panel for indicating a great amount of information which requires a large symbol displaying space. Furthermore, the predetermined indication pattern of FIG. 14 can not show the degree of warning.
The conventional display system of FIG. 15 shows the steps along operation of the keys. However, each screen page shows only a regular pattern, and several keys are necessary to obtain desired information, improvement of which has been needed.
In the conventional display system shown in FIGS. 16A and 16B, the left indication unit 73 in FIG. 16A does not show the engine revolution in the state shown in FIG. 16B. Furthermore, the right indication unit 72 shows the additional information in the indication area 67, and the information indication interferes with the pointer 52 in the state shown in FIG. 16B, degrading the information indication in clarity.